Public Service Commissioner Kevin Cramer upset the North Dakota Republican Party-backed candidate for at-large Representative on Tuesday night. With 84 percent of precincts reporting, Cramer had 53 percent to Brian Kalk's 46 percent.

Cramer is running for the House seat vacated by freshman Rep. Rick Berg (R), who easily won his Senate primary Tuesday against businessman Duane Sand (R).

Earlier this year, North Dakota Republicans picked Kalk, also a public service commissioner, as their endorsed candidate in the GOP primary. A former state party chairman, Cramer ran outside the party endorsement system, giving the GOP's chosen candidate a significant challenge for the first time in recent history.

National conservative groups such as the Club for Growth and FreedomWorks boosted Cramer with independent expenditures on his behalf.